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digital standards systems an integrated approach to engineering standards usage

This document applies to prognostics of aerospace propulsion systems. Its purpose is to define the meaning of prognostics in this context, explain their potential and limitations, and to provide guidelines for potential approaches for use in existing condition monitoring environments.

This document lists recommended noun titles for drawings of support equipment and provides definitions for each. The use of secondary modifiers to distinguish a part from similar parts is also covered.

This recommended practice covers design requirements for silver, copper and nickel brazed joints, primarily for tube connections, for aerospace propulsion systems. The environmental conditions stated herein, and those given in the applicable AMS specifications, provide the limitations of this ARP.

This paper explores some of the many considerations which enter into the choice of a specific spacecraft propulsion system for a particular application. The environment and its influence on propulsion requirements are discussed in general terms, characteristics of several propellant combinations are presented and an example of a typical ambitious mission is used. ...A general conclusion is that the state of the art of spacecraft propulsion technology must advance on a broad front in the time period prior to project definition in order to provide the technological options which allow significant optimization of the complete project propulsion system....A general conclusion is that the state of the art of spacecraft propulsion technology must advance on a broad front in the time period prior to project definition in order to provide the technological options which allow significant optimization of the complete project propulsion system.

THE NUCLEAR turboelectric ion propulsion system operates as follows: 1. A nuclear reactor supplies thermal energy to a vapor boiler. 2. ...Electric propulsion systems can be used in a wide variety of space missions, including satellite sustainers, lunar cargo transport, and interplanetary missions.*

In order to accomplish a lunar landing, all engines and systems must work reliably. Redundant components and system back-up capabilities are provided in the design. ...These crew safety requirements impose many unusual constraints that are not required in launch vehicle or unmanned propulsion system designs. These requirements and their effects on design and operation are discussed and the systems operational experience on Apollo models are presented. ...The Apollo spacecraft has 50 rocket engines arranged in 7 separate and independent systems. During a single mission there are approximately 100,000 rocket engine firings. In order to accomplish a lunar landing, all engines and systems must work reliably.

The selection of the most efficient propulsion system for a V/STOL aircraft presents a difficult problem because of the large number of engine and engine combinations available. ...By utilizing this methodology, it was possible to study most existing concepts of propulsion systems and their applications to many different types of V/STOL aircraft. Based on these studies, some general conclusions regarding the advantages and disadvantages of various propulsion systems are presented, and engine development programs are recommended. ...Based on these studies, some general conclusions regarding the advantages and disadvantages of various propulsion systems are presented, and engine development programs are recommended.

The characteristics of current space propulsion systems are reviewed, including performance, storability, restart, and throttling. Their limitations are discussed with emphasis in the area of long-term storage coupled with high performance.

This paper describes propulsion systems under consideration for orbital maneuvering stages (Space Tug or Orbit-to-Orbit Shuttle). ...It describes the Space Tug/Orbit-to-Orbit Shuttle (OOS) configurations, and the missions to be performed by the Space Tug/OOS. The propulsion system requirements for the Space Tug/OOS main engine and the attitude control systems are described. ...A listing of the propulsion system candidates for this application is provided. Briefly described are existing systems such as Delta, Agena, Centaur, and Transtage.

Wide scope systems studies of V/STOL propulsion were conducted by GE, encompassing the total air vehicle design and its operation in lift, transition, cruise, and STOL modes. ...To determine VTOL propulsion requirements, the author explains the necessity for incorporating the entire air vehicle into the analysis. ...It is felt that the performance indicated necessary by these studies is now attainable by the propulsion industry.

Several advanced propulsion systems with many novel and unusual design features, and transport aircraft incorporating these systems, have been presented to the FAA for type certification. ...To accommodate the certification programs and to ensure that the airplanes and propulsion systems achieve the level of safety intended by the regulations, the FAA will promulgate special conditions covering the novel features which they have identified by meeting with industry and other airworthiness authorities. ...Several advanced propulsion systems with many novel and unusual design features, and transport aircraft incorporating these systems, have been presented to the FAA for type certification. The FAA has determined that many of these features are not addressed by current airworthiness regulations.

Apollo 17 ended the most successful application of rocket propulsion systems in man's history. A total of 23 developmental and manned operational flights were made. ...Over 6 h of manned rocket flights were logged by the spacecraft propulsion systems and approximately one million rocket engine firings were made. One engine failure was encountered on an early unmanned flight as a result of a failure in the guidance programmer which caused the engine to operate in a manner known to cause failures. ...Numerous operational problems and malfunctions were observed; however, system and component redundancy prevented loss of mission objectives and never jeopardized crew safety.

As a result, UAV research and development will contribute to a major portion of spending in the next decades—with a significant emphasis on propulsion technologies. This book will cover several UAV propulsion technologies, ranging from modification of conservative designs to assessing the potential of unconventional arrangements. ...Each chapter provides a glimpse of how researchers are leveraging different fuel types, powerplants, and system architectures in the pursuit of powerful, efficient, and robust UAV propulsion. By developing higher-performing propulsion systems—whether through the refinement of existing technologies like two-stroke heavy-fuel engines and hybrid-electric arrangements or the investigation of new concepts such as dielectric barrier discharge—engineers will be able to increase UAV capabilities for the world’s developing aviation needs. ...By developing higher-performing propulsion systems—whether through the refinement of existing technologies like two-stroke heavy-fuel engines and hybrid-electric arrangements or the investigation of new concepts such as dielectric barrier discharge—engineers will be able to increase UAV capabilities for the world’s developing aviation needs.

Optimization of a Prop-Fan propulsion system for a Mach 0.8, 120 passenger commercial transport has shown the need for relatively high levels of overall pressure ratio, combustor exit temperature, propeller tip speed and propeller disk loading to achieve lowest fuel burn and direct operating costs. ...Comparison of this optimized Prop-Fan propulsion system with an equivalent technology turbofan showed it to have significant mission fuel burn and direct operating cost advantages.

The contribution of improved propulsion systems to the economics and regularity of air transport is examined, with particular reference to developments during the past decade.

ATR with extended precooling (Tout=100K) is examined in more detail. For propulsion systems including different types of engines, running simultaneously the concept of LH2 heat sink capacity concentration for turbojet air precooling is proposed.